C3 Air conditioning help

[frantark10]

Any experience or recommendations as to who can help out with diagnosis/repairs for a factory system on a 77. Been converted to 134, but won't hold gas more than 2 days. Everything works (really cold) with gas in. Have new hose assembly (as the old one looked like a bad plumbers nightmare with hose clamps etc), but was wondering what else I should be looking at based on your experiences. I suspect the evaporator coil (looks like a nasty job), but couldn't detect any leaks or odor while the system was actually cooling.
Before I cause another environmental disaster I'd appreciate your thoughts and opinions. Summer's coming on fast and I'd like not to spend it in a rolling microwave.
Thanks

[Dennis Trayes]

You should be able to put dye in the system to see where it's leaking and there are ultra violet (I think) lights to see it better.

[frantark10]

Thanks Dennis....I'm no HVAC tech so I expect I'll be doing a bit more research on the subject including the dye route.

[Joel Fellman]

My mechanic just repaired the entire air system on our '76. Was leaking at 3 different places! Works fine now - for the first time in 10+ years!! He's in Philly if you're interested.
Then again, there's always Steve at Bryner's.
Joel

[frantark10]

Joel, Three places.....yikes! What were they if I might ask? Let me know who did the work for you. I'm in Morrisville PA, so hopefully your guy isn't too far out of the way for me
.

[Joel Fellman]

at the sight glass, the collector (evaporator core) at the fire wall & a split hose. The mechanic is Charlie at Darby's Service Station: 7228 State Rd. (15 seconds off the Cottman Ave. exit of 95 & turn left onto State Rd.) 215-332-6311. The owner is Rich. Charlie has done almost all my inspections, repairs, maintenance, etc. ever since the '76 came off the 3 year new car warranty. He knows my Vette better than I do! This winter he installed my ZZ4 crate engine & did a great job. He's honest, reliable & reasonably priced. Right now he's working on installing a big block in a '79 & putting some extra muscle in a '70 GTO. Tell him Joel recommended you.

[92RAGTOP]

I'm assuming the compressor is original. If so you may be leaking freon from there (they do sell rebuild kits for these comnpressors if you are adventurous). There is a coupling inside the comp when this wears it begins to leak there are also a few o-rings that are 30 years old by now. When the system is a rest the pressure is low, when the sys is running the pressure is very high, that's when leaks show up. You also have the condensor that's the small radiator in front of the cooling radiator. These go bad often because they are exposed the the weather and stones. Often if there is a leak and you put in dye you can't see the dye at the condensor because of it's location and the cooling fins. The Evaporator is the small radiator looking part usually up under the dashboard or on the firewall. I've never had one of these go bad but they occasionaly do. They make a freon detector tool it's a hand held wand (very expensive) that buzzes when it detects freon. If the evaporator is leaking it will send freon directly to the interior vent system you should be able to stick the wand in the cooling vent on the dash crank up the ac and the buzzing begins. I'm assuming you used the correct o-ring's when you replaced all the hoses ,R12 & 134 are different orings, hoses, and compressor oil? Did you have it converted to 134 by a professional? Did you replace the dryer?
If I were you I would have the system recharged by a A/C mechanic that has a good electronic freon detector. Locate the leak and go from there.After they find the leak they can suck out all the freon while you are replacing parts. I have not had good luck with the dye the freon tool worked for me all the time.
When I buy auto A/C parts I use this guy Hancock Air Conditioning (972) 272-0200 they are located in Dallas, the shipping $ is made up by his good prices and service. They don't repair A/c but they do rebuild compressors and sell parts, I think they are located in Texas. Good Luck.

PS: I lived in Austin,Texas for 10 years the A/C was more important to me than my brakes. I learned how to work on my own system. With 2 kids with jalopies I was alsways working on the A/C to the point that I got my MAC license to buy R12. Glad that's over!!!

[frantark10]

That's why I joined the club in the 1st place. Help like you all have provided me as I get back into this Corvette hobby after a long time away from it. Thanks. At least I know which way to go and what the most likely problems could be. I've now got several things I can check on my own, and if worse comes to worse I've got a resource (Darby's) that comes with a solid reccommendation. Maybe I can get this 77 into some sort of decent shape. Much appreciated gentlemen, and I hope to meet and personally thank you at some future club events. I'm shooting for the Casino Tony's breakfast (as it's close to my home), and the roundup for sure.

[92RAGTOP]

Great, if you get to the point where you need a evacuation compressor, I got one you can borrow. Just send me a PM.

[frantark10]

Thanks again.....I've got access to a compressor, just wish I had access to more time......that's what's always in short supply!